The present invention is directed to a novel and improved refrigerated insulated storage container.
Insulated storage containers are generally used for storage and transport of commodities or other goods which are required to be maintained at or near some given temperature or range of temperatures. Such goods or other commodities may be required to be at either relatively elevated or relatively reduced temperatures (i.e., refrigerated). Such containers are often used in transport of goods by truck, and their use permits the use of ordinary trucks or trailers. That is, use of such containers obviates the need for relatively expensive and complex refrigerated trucks, truck trailers or the like.
Generally speaking, urethane or similar insulation material is utilized in such containers to provide the required insulative qualities for maintaining the desired temperature of the goods to be stored or transported therein. Frequently such containers are provided with separate compartments or the like for carrying a quantity of dry ice or carbon dioxide (CO.sub.2) as a coolant to aid in maintaining the desired temperature of cold goods or commodities during the storage or transport. In the case of the use of carbon dioxide as a refrigerant, the most efficient use of the material dictates that the carbon dioxide vapors be well distributed about the container and about the goods being carried therein.
Heretofore, such containers have been relatively simple in form, presenting generally flat, or smooth interior and exterior surface walls which enclose a quantity of insulation material therebetween. The containers may be either generally rectilinear or generally cylindrical in form, although the rectilinear containers are more frequently used in practice. Accordingly, prior art containers relied primarily upon the effects of gravity and to distribute the cold vapor and air about the container in goods being carried therein.
However, we have found a surprisingly simple and yet effective manner in which to better distribute carbon dioxide vapors about the interior of the container and thus generally about the goods or commodities being carried or stored therein. Moreover, we have devised a method for safely and effectively exiting or exhausting spent carbon dioxide vapor through a simple and yet effective exhaust vent provided in a lower portion of the container. Accordingly, our novel and improved container advantageously optimizes the use of carbon dioxide or, for that matter, of any refrigerant which may be selected for use therewith, by optimizing the air (vapor) flow around and about the interior of the container. Advantageously, our system of air (vapor) distribution about the interior of the container also obviates the need for more expensive and complex mechanical means, such as complex tubing, fans, pumps or the like, for accomplishing such air (vapor) or other refrigerant distribution.
Additionally, insulated storage containers have heretofore generally used a rigid front door usually hingedly attached to a front wall of the storage container for sealingly engaging and closing an access opening therein. Various latching and/or locking means are also employed for releasably latching and closing such doors. However, such doors often present externally protruding hinges, latch parts and the like, such that their use on the containers require some additional amount of floor space inside a semi-trailer or other truck during transit. Such protruding parts may be damaged during handling. Moreover, hinged doors may inadvertantly loosen and/or swing open during handling, as by forklift or the like. This may damage the container, the contents, the forklift, or indeed other equipment. It will be appreciated that such mishaps during handling diminish efficiency of plant operation, because they may require suspending operations in whole or in part and utilizing operating personnel for necessary clean up, repair and the like.
Advantageously, we have provided a further improvement upon prior art storage containers in the form of a flexible door member utilizing a velcro-type of sealing and closure arrangement for releasable closure relative to the container. Our flexible door may also advantageously be fitted substantially flush with the front of the container thus greatly saving required floor space inside of trucks or other trailer vehicles, by permitting such containers to be butted up substantially flush against one another. This also greatly reduces the risk of doors swinging open and causing damage to equipment during handling. Additionally, our flexible door member makes possible substantial weight savings over much heavier rigid door arrangements. Such weight savings can be particularly significant when large numbers of containers are being transported by truck or trailer.